Identification

Title

DAERA Estuarine Fish Survey

Abstract

The DAERA estuarine fish survey is an annual assessment of fish communities in seven river estuaries in Northern Ireland. Data is collected primarily for the purposes of reporting to Water Framework Directive (WFD).

Resource type

dataset

Resource locator

http://www.opendatani.gov.uk/dataset/13c01e4a-0f14-4192-b6c7-08dbdd4a79dc/resource/0ab1f3dd-5f71-4e78-ae7f-340381cea4ca/download/daera-estuarine-fish-survey-data---2018.ods

name: Online dataset

description: A link to the web service or dataset

http://www.opendatani.gov.uk

name: Open Data NI Portal

description: A link to the general host site

Unique resource identifier

code

DAERA-FSH

codeSpace

http://www.daera-ni.gov.uk

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

urn:ogc:def:crs:EPSG::4326

Classification of spatial data and services

Topic category

biota

Keywords

Keyword set

keyword value

Keyword set

keyword value

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2008-01-06

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2009-11-16

Geographic location

West bounding longitude

-7.3833

East bounding longitude

-5.2739

North bounding latitude

55.3492

South bounding latitude

53.9639

Extent

Extent group

authority code

title

reference date

date type

creation

effective date

2009-06-18

code identifying the extent

Irish Sea

Extent group

authority code

title

reference date

date type

creation

effective date

2009-06-18

code identifying the extent

Minches & Western Scotland

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

39E2

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

37E3

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

39E3

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

37E4

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

38E4

Extent group

authority code

title

reference date

date type

revision

effective date

2010-01-01

code identifying the extent

infralittoral

Extent group

authority code

title

reference date

date type

revision

effective date

2010-01-01

code identifying the extent

littoral

Temporal reference

Temporal extent

Begin position

2017-01-01

End position

2020-02-20

Dataset reference date

date type

publication

effective date

2019-02-20

date type

creation

effective date

2019-02-19

date type

revision

effective date

2019-02-20

Frequency of update

annually

Quality and validity

Lineage

The ichthyofauna of each transitional water is sampled using a variety of methods. These include seine netting, fyke netting and beam trawling. This multimethod approach is adopted to ensure that all representative habitats and species are sampled within each estuary. All netting is conducted from a 3.4 m inflatable boat equipped with a 15 hp outboard engine. The seine net is 30 m long by 2 m deep with a 14 mm mesh body and a 5 m long x 3 m deep central panel of 6.5 mm mesh. Seine netting is limited to unobstructed areas with gently sloping banks and is typically deployed in waters less than 1.5 m. Where possible, seine netting is conducted during the two hour period either side of low tide. A fleet of double fyke nets are set in each system. Each trap is 0.5 m high, 2.5 m long with a 10 mm mesh cod end and is joined by a 6 m long x 15 mm mesh leader. The fyke nets are deployed in deeper waters by boat and are laid diagonally across the flow of the river. They are anchored out of the main channel to avoid passing boat traffic and are retrieved after 24 hours. A lightweight shoeless beam trawl is used to sample benthic and demersal fishes. The mouth of the net is 1.5 m wide with a height of 0.5 m, the body of the net is constructed of 14 mm mesh and is 3 m long, tapering to a width of 0.5 m. A 1.0 m long x 0.5 m wide cod end of 6.5 mm mesh is attached to the end of the net. The beam trawl is towed 20 m behind the boat and is deployed and retrieved by hand. Towing speed is between 1 and 2 knots with each tow lasting approximately 5 minutes and covering a distance of between 150 and 300 m. Where possible, all fishes are processed alive in the field and returned to the water. Specimens are identified, measured (mm Total Length (TL)), and weighed (g) before being released. Specimens that cannot be identified in the field are placed in labelled plastic bags and kept cool for transport to the laboratory where they are frozen. Fishes are identified in the laboratory at a later date by reference to published taxonomy texts such as Wheeler (1969), The Fishes of the British Isles and North Western Europe. Scientific and common names of fishes follow those provided in Maitland and Herdson (2009), A Key to the Marine and Freshwater Fishes of Britain and Ireland.All species are counted, and batch weighed to the nearest 0.1 g. Specimens are also measured (mm TL) and grouped into 10 mm size classes. Where large numbers of a particular species are captured, a sub-sample of at least 50 specimens are measured and weighed, the remaining sample is then batch weighed and the total number of individuals estimated using an average specimen weight. The total number of species and their numerical contribution to the total catch is determined for each transitional water. Competency of taxonomic identification is assessed twice yearly by completing the NMBAQC fish component of the ring test programme.

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Data is freely available for research or commercial use providing that the originators are acknowledged in any publications produced.

Constraint set

Limitations on public access

No restriction on access

Responsible organisations

Responsible party

contact position

Data contact

organisation name

Department of Agriculture, Environment and Rural Affairs

email address

Marine.InfoRequests@daera-ni.gov.uk

responsible party role

originator

Responsible party

contact position

Data contact

organisation name

Department of Agriculture, Environment and Rural Affairs

email address

Marine.InfoRequests@daera-ni.gov.uk

responsible party role

custodian

Metadata on metadata

Metadata point of contact

contact position

Data contact

organisation name

Department of Agriculture, Environment and Rural Affairs

email address

Marine.InfoRequests@daera-ni.gov.uk

responsible party role

pointOfContact

Metadata date

2020-02-20

Metadata language